Process of forming half bearing shells and resultant article



July 26, 1932. r c BLOMSTRQM 1,868Q655 PROCESS OF FORMING HALF BEARiNG SHELLS AND RESULTANT ARTICLE Filed Sept. 10, 1928 2 Sheets-Sheet l July 26, 1932. 1.. c. BLOMSTROM 1,868,655

PROCESS OF FORMING HALF BEARING SHELLS AND RESULTANT ARTICLE Filed Sept. 10, 1928 2 sheets sheet 2 II: x

Patented July as, 1932 I I unites rates mmOFFICE- fownLL CJBLOIESTROM, or DETROIT, MICHIGAN, Assrsnon 530- FEDERAL MOGUL conmansion, on ns'rnorr, MICHIGAN, A ooaronarron or MICHIGAN then separate it into' halves and subject itto' other process steps not necessary here to disrnocnss on ron-Mine trans Bananas snnnns AND RESULT'ANT ARTICL Application filed. September 10, 192s. sem No. 304,984.,

ess for forming a half bearing shell and to the resultant article as suclnand has for its ob ject an improved and markedly economical inethodo fformin to the shaperequired the semi-cylindrical bearing shell, which, when thereafterbabbitted or otherwise treated for the production of a bearing surface, may be, and today is, largely used, in cooperation with a companion shell, in gas engines and similar bearing work.

Heretofore it has been the practice to form such a bearing shell, whether of steel, bronze, or other equivalent material by casting or otherwise producing a complete cylindrical blank with appropriate marginal flanges, and

ones, before the shell. could be considered as ready for machining or babbittingtj Some few relatively unsatisfactory articles have also been produced by longitudinally dishing or troughinga piece of metal into cross-sectionally semi-circular shape, and thereafter forming outwardlyextending flanges from its convex side by grinding away or otherwise removinga sufficient amount of metal from its convex surface so as to leave marginal flanges.

Both as regards the expense andin some instances as regards the characteristics ofthe completed article, both of these methods have been found open to objection, and it is the purpose of this invention to obviate this fault as'regards expense, and, as partially preliminary thereto, to reduce the number of the machining operations involved. A very appreci able saving in material may alsobe thus effected. 1

in the drawings: g I

Figure 1 is a perspective of a plane or flat oblong blank of relatively malleable metal, such as steel or bronze, which forms the starting point in the production of the improved article herein dealt with. V

Figure 2 is a perspective showing the second step in the manufacturing operation, to

wit, the tlanging of the marginal edgesof the blank.

Figure 3 is a similar perspective showing the channeling or slight grooving of the each lateral flanges. u 1 7 Figure 4 is a perspective'of thejhalf-bearing shell in its completed form. V I

Figure 5 is an elevational View partly in section showing the position of thefblank a when its fabrication has reached the stage shown inv Figure ia, upon" a suitable forming die,'and with the correspondinglycontoured entering die positioned th'ereabove.

blank immediately adjacent and interiorlyof Figure 6 is a similar sectional elevational view showing the die and its included blank after the descent of the superiorly positioned enteringdie. v Figure *4" is a partly sectional elevational view, taken atright angles to the position shown in Figure 5,,bringingout further'the I actlonofthe enteringdle relatively to the blank before its deformation.

Having decided upon the gauge or desired pleted form, I provide a suitable number of blanks,iinitially of relatively soft metallurgical character and of carefully predetermined dimensions, the length being'that of H the intended interior measurement of the completed blank as shown 1n Figure 4, taken circularly thereof through its middle por :7 wall thickness of the half bea'ring in its com- B along the long sides thereof. The next" stop in the process consistsin'machining grooves C in each marginaledge of the-sur face D which remains after the turning upof the flanges r forming small troughs,

immediately adjacentand within each flange.

I then: position the blank as thus altered and I fabricated, upon the lower'or receiving die'E,

which is provided with activeconcave surfaces F and GJOf similar curvature to the, intended outer curvature of the completed half bearings, one end "being positioned against a stop or pin P to assure its correct positioning thereover. 1:.then bring down thereupon with adequate force the entering die Q, which is provided with arounded con-f v-ex'surface of the same curvature as thatof the inner face of the half'bearing which it .is desired to make; This effects the bending of both the intermediate Web portion D'of the blank and of the flanges B to the curvature desired, and the now formed blank may be ejected from the receiving die E in which it is naturally quite firmly seated, by means of the knock-out punch J. The provision in the ultimate outer or convex surface of the half bearing of the marginal grooves C etfects an undercutting contouring of that face of the bearing, and makes it a comparatively easy matter to effect a finishing machining, as by grinding, of the surface, preparatory to the further and finishing treatment of the half bearing. This is brought out with particular clearness in Figures 4 and 6. However, if the bending up of the flanges B can be made sharply angular enough as regards the lines of meeting of their interior surfaces with the intermediate surface D, so as to in itself give an undercut eflcct to these angles even after the blank has been bent to semi circular form, this described second step of the process may be omitted.

Unless a very ductile grade of metal is used, there is a tendency on the part of the half hearing when completed for its marginal flanges, though satisfactorily bent near the ends L, to bulge somewhat near its center portion as M. To counteract this. I very slightly taper the sides of the receiving die E from top to bottom as indicated at N, in Figure 5, so that when the circularly deforming movement of the blank is at an end and the end portions of the flanges as L are bent to just the degree required, the intermediate portion of the flanges, as M, will be bent slightly more than required. so that when the half-bearing is released and ejected from the die, the tendency of the central portion M of the flanges to spring back somewhat can be relied upon to bulge them out once more to just the proper degree and so as to be in ultimate alignment with end portions L. Actually this variance or tapering in the bearing of the receiving die E. which is indicated in exaggerated form at N, need be but a very few thousandths of an inch. and it is not always necessary to resort to this, a receiving die member with parallel rather than inclined surfaces being adequate.

Dependent upon the initial degree of hardness of the steel, bronze or other metal used, and upon the desired rigidity of the completed half bearing shell. it may be desirable, after the half bearing shell has been fully formed as above described, to harden the component metal in any one of several well known ways which it is not necessarv here to discuss. V

Having described my invent-ion, what- I claim is:

l. The process of forming a half-bearing shell, which consists in laterally flanging a plain blank of selected dimensions, forming grooves lengthwise of those lateral edges thereof next inside of the flanges as formed,

positioning the flanged and machined blank over a seniicircularly concaved receiving die, and subjecting the blank as thus positioned to the impact of a correspondingly contoured entering die.

The process of forming a half-bearing shell, consis. -g in forming upstanding flanges from the lateral edges of a flat blank of selected dimensions, forming grooves along the edges of that face thereof then flanked by said flanges, and subjecting the blank as thus modified to the semicircularly forming impact of a pair of cooperating die members.

2 The process of forming a half-bearing shell, consisting in forming into upstanding flanges the lateral edges of a flat blank, grooving that surface thereof immediately adjacent the intersection of the formed flanged edges with the intermediate plane surface thereof, and subjecting the thus contoured blank to the semicircularly bending action of a pair of cooperating and complementarily formed die members.

4.. The process of forming a half-bearing shell, which consists in laterally fianging a flat blank, forming relatively narrow grooves in the then concaved facethereof along the lines of union of the flanges and the intermediate web, and subjecting the blank as thus contoured to the semicircularly bending action of a pair of complementarily formed die members.

5. The process of forming a half-bearing shell, consisting in bending the lateral edges of an initially flat blank into sharply right angular relation to the intermediate surface of the blank flanked by them, positioning the blank ove a concaved forming die having slightly tapered side walls, whereby the intermediate portions of the flanges are inbent slightly in excess of the degree ultimately desired while confined within the die recess, and. subjecting the blank as thus positioned to the bending pressure of a correspondingly curved entering die.

In testimony whereof I sign this specifica tion.

LONELL C. BLOMSTROM. 

